Limited amounts of arable land and adverse environmental conditions, whether natural or man made, have resulted in the use for many years of closed environment structures. These have for the most part been greenhouses of the most basic type. However, over the years methods of plant husbandry and improved structures of the greenhouse type have been constantly under development.
One relatively recent advance in controlled environment husbandry has been the use of nutrient film techniques. In general terms these techniques involve the contacting of the bottom of a plant root system with a thin stream of nutrient solution. The solution soaks up through the remainder of the root system by wicking or capillary action. A great many external influences affect the relatively sensitive nutrient film technique. Efforts are now underway to control various of these influences to improve both the technical aspects and the economics of the systems.
In nutrient film plant propagation techniques it is commonly the case that seedlings are propagated in plant nursery or in a nursery section of a production facility and are then at an appropriate time transplanted into a production area of the facility. Seed germination and the initial growth period for young plants require substantially different conditions than those appropriate for later growth to maturity. For example, the space requirements for the seedlings are clearly substantially less than is the case for mature plants. Similarly, the amount and content of nutrient solution may vary in the two situations. For these and other reasons the transplant procedure is utilized.
There are a number of problems inherent in the transplant procedure. For example, adequate spacing of plantings must be maintained to allow equal access of light to all seedlings and to prevent the root system of one planting from entangling with the root system of the next. The latter situation if allowed to occur results in a substantial shock to the plants when the root systems are separated. The plant growth is consequently set back.
As well, it is essential to provide proper nourishment in the nutrient film and to ensure that the plantings have to as great an extent as possible equal access to the nutrient solution.
Various types of trays, boxes and the like currently utilized for seedling propagation have been found to be inadequate in various of the areas discussed. Accordingly, there is a need for an improved seedling propagation assembly. Against this background such an assembly is provided.